1. Field of the Invention
This invention relates to treatment of tissue specimens and, more specifically, to the treatment of the tissue specimens in vivo.
2. Description of the Related Art
The prior art discloses devices and methods of isolating a tissue specimen while it remains in surrounding tissue. The prior art also discloses devices and methods of ablating or otherwise damaging a non-isolated tissue specimen in vivo. However, the prior art does not disclose, suggest, nor motivate combining the two concepts into one method or device. Additionally, the prior art does not disclose any synergistic effects of combining the two concepts.
It is disclosed in a paper entitled xe2x80x9cThe Loop Electrode: A New Device For US-guided Interstitial Tissue Ablation Using Radiofrequency Electrosurgeryxe2x80x94An Animal Study,xe2x80x9d T. Lorentzen et al., Min Invas Ther and Allied Technol 1996:5:511-516, that a radiofrequency loop is used to perform interstitial tissue ablation. The device was inserted into calf livers and rotated to interstitially cut off lesions. The paper reviews minimally invasive tissue ablation techniques, such as intraoperative cryosurgery and percutaneous methods such as laser, microwaves, radiofrequency electrosurgery, and injection of ethanol or hot saline. The paper also reviews high-focused ultrasound as an example of a non-invasive method. The paper does not disclose, suggest, nor motivate combining the use of a radiofrequency loop with other tissue ablation methods.
A procedure is disclosed in a paper entitled xe2x80x9cInterstitial Hyperthermia Of Colorectal Liver Metastases With A US-guided Nd-YAG Laser with a Diffuser Tip: A Pilot Clinical Study,xe2x80x9d C. Nolsxc3x8e et al., Radiology, 1993; 187:333-337, that involves placing a laser fiber in the center of a tumor and irradiating the tumor to achieve hyperthermia ablation. It is also disclosed to use ultrasound to monitor the temperature of the tumor during the method. The paper discloses a charred border region about the tissue specimen and a coagulated region beyond the charred border. The paper does not disclose any concerns associated with ablating a non-isolated tissue specimen. The paper does not disclose, suggest, nor motivate combining the use of lasers with other tissue ablation methods.
It is disclosed in a paper entitled xe2x80x9cPhototherapy of Tumors,xe2x80x9d S. G. Brown, World J. Surg. 7, 700-709, 1983, the use of the chemical hematoporphyrin derivative (HpD) in conjunction with a dye laser for tumor therapy. The HpD/dye laser method is not thermal, as is the case with most laser methods, but depends on the production of singlet oxygen by activated HpD. The paper discloses the promise of the HpD/dye laser methodsxe2x80x94but with no disclosure, suggestion, or motivation to isolate the tissue specimen prior to treatment. The paper discloses the problems associated with unacceptable damage to surrounding tissue during thermal laser methods.
It is disclosed in a paper entitled xe2x80x9cClinical Thermochemotherapy: A Controlled Trial In Advanced Cancer Patients,xe2x80x9d F. K. Storm et al, Cancer 53:863-868, 1984, to combine hyperthermia and chemotherapy for increased drug uptake of cancer cells. The hyperthermia was administered using a magnetrode magnetic-loop induction device. The paper does disclose the beneficial of preserving the tissue surrounding the tissue specimen, which in the disclosed method is due to coincident vascular occlusion. It does not disclose, motivate, or suggest direct methods of severing vascular connections between a tissue specimen and surrounding tissue, in conjunction with other methods of tissue specimen ablation.
It is disclosed in a paper entitled xe2x80x9cLiver Photocoagulation With Diode Laser (805 nm) Vs Nd:YAG Laser (1064 nm),xe2x80x9d S. L. Jacques et al., SPIE Vol. 1646 Laser-Tissue Interaction III (1992), p. 107-117, that laser treatment results in radially expanding regions of tissue damage. The paper does not disclose, suggest, nor motivate isolating the tissue specimen targeted for necrosis and any result that may have with reducing damage to surrounding tissue.
It is disclosed in a paper entitled xe2x80x9cMR Imaging Of Laser-Tissue Interactions,xe2x80x9d F. A. Jolesz, Radiology 1988; 168:249-253, that thermal transfer and damage to surrounding tissue during hyperthermia treatment should be monitored. The paper also discloses that circulatory cooling, among other parameters, affects energy deposition. The paper does not disclose, suggest, nor motivate that isolating the tissue specimen prior to hyperthermia treatment. This information is similarly disclosed in a paper entitled xe2x80x9cTemperature Mapping With MR Imaging Of Molecular Diffusion: Application to Hyperthermia,xe2x80x9d D. L. Bihan, Radiology 1989; 171:853-857.
Therefore, the prior art discloses damage occurs to tissue surrounding a tissue specimen to be treated. What is needed is a device and method for reducing damage to the surrounding tissue. What is also needed is a device and method with increased efficiency for damaging the tissue specimens.
In an aspect of the invention, a tissue specimen that is disposed in surrounding tissue is treated. The treatment comprises an isolation step and a damaging step. During the isolation step, the tissue specimen is isolated from the surrounding tissue by at least partially severing the tissue specimen from the surrounding tissue. Next, the tissue specimen is damaged.
In an aspect of the invention, the isolating step further comprises the step of moving a tissue specimen isolating tool about the tissue specimen. In a further aspect of the invention, the tissue specimen isolating tool comprises a radio frequency energized wire. The treatment process may include the step of applying a tool charged with radio frequency energy to the tissue specimen.
In aspects of the invention, the damaging step may comprises applying ionizing radiation to the tissue specimen, cutting the tissue specimen, thermally treating the tissue specimen, chemically treating the tissue specimen, or sealing an outer boundary of the tissue specimen.
In an aspect of the invention, a device for treatment of a tissue specimen in surrounding tissue comprises an operational portion, a tissue severing tool, and a tissue specimen damager. The tissue specimen isolating tool and the tissue specimen damager are disposed at the operational portion.
In a further aspect of the invention, a radio frequency generation source is functionally connected to the tissue specimen isolating tool.
In an aspect of the invention, the tissue specimen isolating tool of the treatment device comprises a cutting member that is extendable to an outwardly radially bowed position about the operational portion. In a further aspect of the invention, a cutting member radio frequency generation source is functionally connected to the cutting member.
In an aspect of the invention, the tissue specimen damager of the treatment device comprises at least one metal member extending from the operational portion and being functionally connectable to a metal member radio frequency generation source.
In aspects of the invention, the tissue specimen damager may comprise an ionizing radiation director, a tissue specimen cutter, a thermal treatment system, or a chemical introduction system.